Understanding trends in genitalChlamydia trachomatiscan benefit from enhanced surveillance: findings from Australia

Abstract

The sexual health service network suggests a moderate increase in chlamydia prevalence in young heterosexuals tested at sexual health services, in contrast to the steep increase shown by notifications. This highlights the caution needed in interpreting chlamydia trends without a corresponding testing denominator.

A new approach to estimating trends in chlamydia incidence

“…First, there has been an increase in the number of notifications 10. Second, prevalence as notified by the ACCESS sentinel surveillance system at sexual health services across Australia11 showed increasing trends in young people aged 15–29 between 2006 and 2010—which when expanded to the whole time period will be more pronounced. Third, positivity among 15–24-year-old men, as calculated by notification-to-testing ratio has remained roughly constant.…”

“…However, the systematic increase in testing rates in Australia over the last decade is believed to be largely responsible for the increasing number of notifications 11. Despite increases, testing rates still remain relatively low with only about 10% of the most affected age group, 16–29-year-olds, tested each year 12.…”

Genital warts and chlamydia in Australian women: comparison of national population-based surveys in 2001 and 2011

“…For chlamydia, national surveillance data, based in most jurisdictions on laboratory notifications, have demonstrated substantial increases in diagnoses across most age groups, but particularly among those aged 15–29 years 1. Although mostly due to increased testing, assessments among sexual health clinic attenders suggest that there is a real, albeit small, component due to increases in prevalence 7. For genital warts, evaluation has relied on a network of sexual health clinics which have reported large declines in first diagnoses of genital warts in the cohorts of young women eligible for free HPV vaccination 8 9…”

Management rates of sexually transmissible infections by Australian general practitioners, 2000–2012

“…This paper reported a 111.5% increase in Medicare-rebated chlamydia testing (as a measure of general practice test orders) from 2005 to 2010, compared with only a 43% increase in prevalence as measured by national notification rates over the same period. 13 Infection with HSV is not notifiable in Australia. Based on data collected in 2000,~1 in 8 Australians aged 25 years and over has serological evidence of Type 2 infection and furthermore, three out of four Australians also have Type 1 infection, which may cause anogenital symptoms.…”